We know that some environmental changes are hard to see, especially those changes that only show their true effects over the long-term. The global difference that fertiliser-use has brought started at the beginning of the 20th century; granted, most of us weren’t around before widespread synthetic nitrogen production, but we should still certainly be aware of the massive change it’s had on our earth.
Our seas and other bodies of water have been altered since nitrogen fertiliser became popular; so has our air. This means our earth, gaseous atmosphere, and waters have been affected; this isn’t something to brush off.
There are positives and negatives to the use of fertiliser, but sometimes even the positives can create more problems than solutions.
Interestingly, the very thing that synthetic fertiliser set out to solve, feeding the population, has created a bit of cyclical problem. Our growing population is well-fed; but that’s exactly it. It’s a growing population that continuously expands year on year. We need more food, but since we can’t increase our farmable land, more and more nitrogen must be produced. A bigger population translates directly to more and more air pollution.
This doesn’t mean that nitrogen fertiliser is to blame; creating food for those who need it is a great thing, but creating a suitable life for our huge population shouldn’t necessarily be a farmer’s worry.
The process of synthetic nitrogen fertiliser creation was discovered by Haber and Bosch, two German scientists of the early 20th century. Their method used a catalyst with high pressure and temperatures to help nitrogen bind with naturally occurring hydrogen. This forms ammonia, from which nitrogen fertilisers can be created.
Often, too much fertiliser is applied to soils, and the run-off can poison our waterways. In seas, too much nitrogen can benefit some organisms and limit others. Algae can grow freely and rampant on the water’s surface, leaving the eco-system beneath the surface with no light to survive or to absorb important vitamins from.
Without nitrogen fertilisers however, our land can’t produce the huge commercial quantities that we’re used to as a society. Harvesting crops means that the naturally occurring nitrogen in plants, which would usually be re-absorbed into the soil as the plant dies, doesn’t have a way of returning to the earth. Soil that is lacking in nitrogen won’t produce the same volumes as nitrogen-rich land would.
The Haber-Bosch process was hailed as a glorious way of making nitrogen out of thin air (of course, nitrogen literally is our air, mind you) but it doesn’t mean it’s without consequence. Better education of why, how, and when we should use synthetic nitrogen fertiliser is something that could help us to counteract the negative effects of fertiliser-usage and increase the many positives.
Teagasc has some information on the different types of fertiliser available, which you can read up on here.